Technique sensitivity in bonding to vital, acid-etched dentin

Area of Science:

• Dental Materials Science
• Adhesive Dentistry
• Biomaterials Research

Background:

• Vital dentin requires moisture to prevent collagen matrix collapse after acid-etching.
• In vitro validation of moist bonding techniques may not fully replicate in vivo conditions.
• Understanding the impact of moisture control on resin-dentin interfaces is critical for clinical success.

Purpose of the Study:

• To hypothesize that moist bonding in vivo yields results comparable to in vitro bonding.
• To investigate the effects of excessive drying or wetting on vital acid-etched dentin during bonding.
• To evaluate the integrity of resin-dentin interfaces under varying moisture conditions.

Main Methods:

• Resin-dentin interfaces were bonded using a moist bonding technique (Excite DSC) in vitro and in vivo.
• Transmission electron microscopy (TEM) was employed to examine interface morphology and tracer penetration.
• In vivo specimens were subjected to controlled excessive drying and wetting conditions.

Main Results:

• Silver deposition patterns were consistent in adhesive and hybrid layers formed in vitro and in vivo.
• Excessive drying in vivo prevented the formation of a hybrid layer.
• Excessive wetting in vivo led to increased nanoleakage and water tree formation.

Conclusions:

• Moist bonding techniques in vivo demonstrate similar outcomes to in vitro bonding.
• Maintaining optimal moisture balance is essential for effective hybrid layer formation and interface integrity.
• Deviations from optimal moisture levels, particularly excessive wetting, negatively impact resin-dentin bond quality in vivo.